Control device suitable for use in an apparatus for reproducing video, audio and accompanying characters

Abstract

A control device suitable for use in a sing-along or karaoke apparatus has a rotary encoder coupled to a selector knob through a transfer mechanism, such as gears. When the selector knob rotates, the rotary encoder generates pulse signals for each rotation of the selector knob. The number of pulses may depend upon a gear ratio of the transfer mechanism. The control device is used, for example, to scan and select music titles stored in a ROM cartridge or other suitable storage medium. The control device may be integrated with an apparatus for controlling the start or stop function. The control device provides a design flexibility due to its compact design.

What is claimed is: 
     
       1. A control device suitable for use in an apparatus for reproducing pre-recorded performance and title information of a plurality of music pieces, the control device comprising: a knob which is rotatable about an axis:;   an actuating member slidably moveable in a direction of the axis of the knob;   a rotation encoder which is responsive to a rotation motion of the knob, wherein the rotation encoder produces a pulse signal corresponding to the rotation motion of the knob, and wherein the pulse signal triggers the apparatus to scan the titles of the plurality of music pieces;   a transfer mechanism having a predetermined transfer ratio, wherein the transfer mechanism includes a first gear coupled to the knob and a second gear coupled to the rotation encoder, in which the first gear and the second gear directly engage each other to transfer the rotation motion of the knob to the rotation encoder; and   a switch which is mounted substantially underneath the actuating member and is activated by depressing the actuating member of the knob, downwardly along the axis of the knob wherein the switch generates a signal to trigger the apparatus to select a music piece or to start/stop playing a music piece.   
     
     
       2. A control device according to claim 1, wherein the actuating member comprises a pair of legs protruding downward to activate the switch when the actuating member is depressed. 
     
     
       3. A control device according to claim 1, wherein the knob has a spring disposed underneath the actuating member to maintain an un-depressed state when no pressure is applied onto the actuating member. 
     
     
       4. A control device according to claim 3, wherein the switch is located substantially adjacent to the rotation encoder to maintain a compact design of the control device. 
     
     
       5. A control device according to claim 1, wherein the predetermined transfer ratio is a number greater than 1, so that the rotation encoder produces more than one pulse signal for each revolution of the knob. 
     
     
       6. A control device according to claim 1, wherein the predetermined transfer ratio is 2. 
     
     
       7. A control device according to claim 6, wherein the rotation encoder produces one pulse signal for each tooth of the second gear rotated. 
     
     
       8. A control device according to claim 1, wherein the actuating member is disposed within the knob, in which the movement of the actuating member is independent of the rotation of the actuating member. 
     
     
       9. A control device suitable for use in an apparatus for reproducing pre-recorded performance and title information of a plurality of music pieces, the control device comprising: a knob which is rotatable about an axis;   an actuating member slidably moveable in a direction of the axis of the knob;   a rotation encoder which is responsive to a rotation motion of the knob, wherein the rotation encoder produces a pulse signal corresponding to the rotation motion of the knob;   a transfer mechanism having a predetermined transfer ratio, wherein the transfer mechanism is coupled between the knob and the rotation encoder to transfer the rotational motion of the knob to the rotation encoder; and   a switch which is mounted substantially underneath the actuating member and is activated by depressing the actuating member of the knob downwardly along the axis of the knob.   
     
     
       10. A control device according to claim 9, wherein the transfer mechanism includes a first gear coupled to the knob and a second gear coupled to the rotation encoder, in which the first gear and the second gear directly engage each other to transfer the rotation motion of the knob to the rotation encoder. 
     
     
       11. A control device according to claim 9, wherein the transfer mechanism includes a plurality of pulleys and a belt wound around the plurality of pulleys, wherein the a first pulley of the plurality of pulleys is coupled to the knob and a second pulley of the plurality of the pulleys is coupled to the rotation encoder. 
     
     
       12. A control device suitable for use in an apparatus for reproducing pre-recorded performance and title information of a plurality of music pieces, the control device comprising: a knob which is rotatable about an axis and slidably moveable in a direction of the axis of the knob;   a rotation encoder which is responsive to a rotation motion of the knob, wherein the rotation encoder produces a pulse signal corresponding to the rotation motion of the knob;   a transfer mechanism having a predetermined transfer ratio, wherein the transfer mechanism is coupled between the knob and the rotation encoder to transfer the rotation motion of the knob to the rotation encoder; and   a switch which is mounted substantially underneath the actuating member and is activated by depressing the knob in the direction of the axis of the knob.